Connor Campbell, a financial analyst at SpreadEx, says in an email: "Investors are assumedly shaken by the events in Manchester yesterday evening, combined with the continued effects of the Tories' election wobble."

The pound has barely moved following data that showed public sector net borrowing increased by £1.2 billion in April compared to the same time in 2016.

Sterling is down 0.20% against the euro at 10.10 a.m. BST (5.10 a.m. ET):